Ship with elastic structure parts, preferably tug



March 2, 1965 a. w. LEHMANN 3,171,378

SHIP wrm Eus'nc STRUCTURE PARTS, PREFERABLY 'ruc Filed Sept. 14. 1962 (TT l E; L;

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GUENTHER W. LEHMANN AGENT United States Patent Ofitice 3,171,373Patented Mar. 2, 1965 3,171,378 SHIP WITH ELASTIC STRUCTURE PARTS,PREFERABLY TUG Guenther Wolfgang Lehmann, 98 Duke of Gloucester Sh,Annapolis, Md. Filed Sept. 14, 1962, Ser. No. 224,284 8 Claims. (Cl.11465) Tugs are usually equipped with genders, particularly at the bowin order to absorp the impact when the tug contacts the hull of a ship.

Fenders consist usually of rubber tires or hawser work wound around thebow and at the sides of a tug, mostly above the waterline. When towingsubmarines it is required to extend the shock absorbing areasubstantially below the waterline in order to prevent damage to tug andsubmarine in view of the bulging shape of submarines below thewaterline. Tugs with a specially designed rubberhose have been equippedin that way and the rubberhoses are attached to the hull by rope andshackles. Since these rubberhoses are outside the actual hull of thetug, an irregular surface produces eddies and an unfavorable shipsresistance when the tug is cruising at high speed to the towing scene.

It is the objective of this invention to provide adequate shockabsorbing qualities of the hull where required and at the same time toprovide a smooth surface similar to a regular hull shape. This problemis solved in accordance with this invention when the hull sectionforward of the collision bulkhead is built entirely of rubber or similarshock absorbing material with the same shape as an ordinary hull and byproviding specially designed attachment means between the elastic andthe solid portion of the hull.

The above and other features of the invention will become more apparentin the following detailed description of certain preferred embodimentsthereof, taken in conjunction with the accompanying drawing wherein FIG.1 is a inboard section of the bow;

FIG. 2 is a cross section of FIG. 1 along lines A-A;

FIG. 3 is a plan view of FIG. 1; and

FIG. 4 shows a raked bow with an upper elastic bow portion.

A tug 1 has a bow 2 built of rubber or other shock absorbing material,hereafter called elastic material, attached to a collision bulkhead 3which is built of steel or wood in customary fashion, hereafter calledrigid material, the bulkhead defining a forepeak with the bow.

The bulkhead 3 has tongues 4 which serve as attachment means to similarelastic tongues 5 of the elastic bow 2. Impact force 5 may act in anydirection, as shown by longitudinal component 6, a transverse component7 and a vertical component 8. Transverse and longitudinal components 6,7 are transferred by elastic tongues 5 to rigid tongues 4. The verticalcomponent 8 is transferred through elastic deformations of the how 2 andtongues 5 to tips 9 of rigid tongues 4. Solid vertical brackets 10 andelastic vertical brackets 10a are mounted, respectively, betweenadjacent tongues 4 and 5 to assure proper transfer of the component 8and resultant moments.

The lower portion 11 of the how 2 extends well below lower edge 12 ofthe rigid bulkhead 3 and aft to 13, and cavities 14 in the lower portionof the elastic how 2 contribute to the absorption of impacts when theyoccur at that area. The portion 15 above the deck 1a may be built alsofrom elastic material with ribs 16 and an elastic flat 17 attached to asolid deck tongue 18. Vertical solid brackets 19, 19a serve as rearattachment means of the portion 15 against the solid tug structure.

Bitts 24 and similar heavy forces transmitting equipment which requiresolid foundations are mounted on the solid tug structure behind theelastic bow structure 2.

As illustrated in FIG. 4, a ship with a raked how 26 has an upperelastic bow portion 27 extending up to or below the waterline 28 withthe hawsepipe 29 in the limits of the rigid hull structure 30.

It is understood that the stern or any other part of a tug may be builtof elastic material in the fashion as described, with due considerationto the prevailing shape of the hull.

It is furthermore understood that the herein described compositestructure of elastic and solid material may also be applied to any otherhull area and extension thereon. A composite structure built inaccordance with this invention, preferably with reference to an elasticbow structure, will have a beneficial effect in case of collisions,resulting in minor damages to ships involved in an accident.

Existing tugs or ships may easily be equipped with an elastic bow bysimply removing a bow portion forward of the collision bulkhead andreplacing it with an elastic structure as described herein.

While the invention has been described and illustrated in connectionwith certain preferred embodiments, it will be understood that manyvariations and modifications may occur to those skilled in the art,particularly after benefiting from the present teaching, withoutdeparting from the spirit and scope of this invention as defined in theappended claims.

I claim:

1. A vessel comprising a hull including a main portion and a how, acollision bulkhead mounted transversely of said hull and defining aforepeak with the how, the main hull portion and the bulkhead being ofrigid material, and the bow, at least above the vessels waterline, beingof elastic material, a plurality of vertically spaced rigid tonguesextending from said bulkhead towards said elastic bow, rigid verticalbrackets mounted between the rigid tongues, a plurality of verticallyspaced elastic tongues extending from the elastic bow towards saidbulkhead, said rigid and elastic tongues being in registry, andregistering ones of said said tongues being connected to each other, andelastic vertical brackets mounted between the elastic tongues.

2. The vessel of claim 1, wherein the rigid tongues extend into theelastic tongues for connection therewith.

3. The vessel of claim 1, wherein the rigid and the elasltic tonguesextend about equidistantly into the forepea 4. The vessel of claim 1,wherein the elastic bow comprises a lowermost portion with an extensionbelow and aft of the collision bulkhead.

5. The vessel of claim 4, wherein the lowermost bow portion definescavities within its body.

6. The vessel of claim 1, wherein the elastic bow extends about to thewaterline of the vessel, and further comprising a hawsepipe mounted inthe rigid main hull portion adjacent the elastic bow portion.

7. The vessel of claim 1, further comprising a deck extendingtransversely of the main hull portion to the collision bulkhead, a rigiddeck tongue extending from the deck over the forepeak, a pair of rigidupright brackets rising above the deck, each of said upright bracketsbeing mounted adjacent opposite sides of the main hull portion, saidelastic bow portion rising above said deck and being aflixed to saidupright brackets, an elastic flat deck portion extending inwardly of thelast-named bow portion in registry with the rigid deck tongue, and aplurality of elastic vertical ribs extending inwardly of the last-namedbow portion to the rigid deck tongue.

8. A vessel comprising a hull including a main portion and a bow, acollision bulkhead mounted transversely of said hull and defining aforepeak with the bow, the main hull portion and the collision bulkheadbeing of V a I rigid material, and the bow down to about the vesselswaterline being of elastic material, the rigid main hull 7 portionextending forwardly of the collision bulkhead Donovan t Oct. 25', 1910Haase Oct. 15, 1929 4 V r r Waller Dec. 28, 1943 Baggerud .4; Feb. 27,-1951 Rutledge May 24, 1960 FOREIGN PATENTS Great Britain V V AD. 1899Great Britain May 17, 1939 Great Britain Jan. 21, 1941 France June 6,1908 Switzerland Feb. 17, 1930 Germany Feb. 21, 1957

8. A VAESSEL COMPRISING A HULL INCLUDING A MAIN PORTION AND A BOW, ACOLLISION BULKHEAD MOUNTED TRANSVERSELY OF SAID HULL AND DEFINING AFOREPEAK WITH THE BOW, THE MAIN HULL PORTION AND THE COLLISION BULKHEADBEING OF RIGID MATERIAL, AND THE BOW DOWN TO ABOUT THE VESSEL''SWATERLINE BEING OF ELSTIC MATERIAL, THE RIGID MAIN HULL PORTIONEXTENDING FORWARDLY OF THE COLLISION BULKHEAD ADJACENT THE VESSEL''SWATERLINE, AND A HAWSEPIPE MOUNTED IN THE FORWARDLY EXTENDING RIGID MAINHULL PORTION.